The specific gravity 60/60°F scale compares the relative density of a given liquid with that of water at 60°F (15.6°C).Material: Soda glass Steel shot ballast Synthetic wax resinRange: 0.200 S60/60°FAccuracy: 0.004 S60/60°FDivisions: 0.002 S60/60°FOverall Length: 250mmBulb Diameter: 18 - 20mmApprox. Weight: 42g (including 11g protective plastic tube)